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1.
梁爽  孙正兴 《软件学报》2009,20(5):1301-1312
为了解决草图检索相关反馈中小样本训练、数据不对称及实时性要求这3个难点问题,提出了一种小样本增量有偏学习算法.该算法将主动式学习、有偏分类和增量学习结合起来,对相关反馈过程中的小样本有偏学习问题进行建模.其中,主动式学习通过不确定性采样,选择最佳的用户标注样本,实现有限训练样本条件下分类器泛化能力的最大化;有偏分类通过构造超球面区别对待正例和反例,准确挖掘用户目标类别;每次反馈循环中新加入的样本则用于分类器的增量学习,在减少分类器训练时间的同时积累样本信息,进一步缓解小样本问题.实验结果表明,该算法可以有效地改善草图检索性能,也适用于图像检索和三维模型检索等应用领域.  相似文献   

2.
提出一种基于SVM和Adaboost集成学习相结合的相关反馈算法。在相关反馈过程中选择最具信息的样本训练支持向量机,可以有效减少相关反馈的次数和所需学习样本的数量,通过两者的互补来有效地提高图像检索的精度。最后提出Adaboost算法对SVM分类器进行加权投票,这样进一步提高了图像检索的性能。实验表明,该方法较好地解决了图像检索中的小样本选择问题,能够显著提高图像检索的效率和性能。  相似文献   

3.
为缩小"语义鸿沟",探讨了将支持向量机(SVM)应用于视频语义检索,提出了利用多变量支持向量机回归方法(SVR)进行语义自动标注,再将SVM分类应用于关键帧的语义检索的反馈中,改进了传统的SVM反馈方法.一方面记忆并累加样本集,优化负例选择,平衡正负样本数目,使训练集样本保持动态增长的平衡状态;另一方面,保存每次满意查询的SVM模型,使本次的反馈信息得以继续使用,从而建立SVM反馈的长期记忆机制.实验结果表明,与基于内容的SVM反馈检索相比,改进后的基于SVM反馈的视频语义关键帧检索的准确率和检索效率都有所提高.  相似文献   

4.
相关反馈技术是基于内容图像检索研究的热点。本文针对现有SVM相关反馈中假定相关图像的所有特征为相关这一不完全准确假设,提出了MISVM短期机器学习相关反馈方法。该方法采用多示例学习方法确定图像中每个特征的相关程度来提高SVM的分类准确性;在此基础上,为进一步提高系统反馈速度与准确率,通过保存以前训练好的分类器和反馈样本,提出了基于LMISVM长期机器学习的相关反馈方法。文中提出的两种方法与其它方法进行了比较实验,结果表明该方法优于其它方法。  相似文献   

5.
为进一步提高基于内容的医学图像检索性能,本文对相关反馈算法和全局特征进行研究。将基于模糊区域特征的图像检索和相关反馈算法与基于SVM的相关反馈算法结合起来,对复杂的区域特征采用基于模糊区域特征相关反馈算法,对全局特征采用能同时使用正例和负例图像的基于SVM的相关反馈算法,提出联合相关反馈算法。实验结果表明,采用这些方法后,检索结果有了很大的提高。  相似文献   

6.
一种新的基于SVM的相关反馈图像检索算法   总被引:4,自引:0,他引:4  
提出了一种新的基于支持向量机(SVM)的相关反馈图像检索算法。实验结果表明,该算法在一定程度上解决了基于SVM的相关反馈图像检索中存在的样本不足的困难,提高了系统的检索性能。  相似文献   

7.
提出一种基于改进优势集聚类的无监督学习图像检索方法,使用有记忆的SVM相关反馈将底层视觉特征和高层语义相结合,并充分发掘图像之间的相似性以得到更接近用户检索要求的结果,实验结果表明,该方法能快速收敛于用户的查询概念,在图像检索系统的准确率和反馈次数方面表现出一定的优越性.  相似文献   

8.
梁竞敏  唐斌 《微计算机信息》2012,(5):174-176,173
语义图像检索已成为解决简单视觉特征和用户检索高级语义之间存在的"语义鸿沟"问题的关键,本文试图提出一种基于SVM和Adaboost集成学习相结合的相关反馈算法。在相关反馈过程中选择最具信息的样本训练支持向量机,可以有效减少相关反馈的次数和所需学习样本的数量,通过两者的互补来有效地提高图像检索的精度。最后提出Adaboost算法对SVM分类器进行加权投票,这样进一步提高了图像检索的性能。实验表明,该方法能较好地解决了图像检索中的小样本选择问题,并能显著提高图像检索的效率和性能。  相似文献   

9.
宋贤霞 《福建电脑》2011,27(6):63-64
将主动学习算法引入到图像检索中,以SVM作为分类器提出一种新的相关反馈算法,有效解决相关反馈技术中固有的小样本问题,提高了SVM的分类性能,从而使检索系统的检索精度有一定的提高.  相似文献   

10.
基于模板匹配和SVM的草图符号自适应识别方法   总被引:4,自引:0,他引:4  
在草图符号的自适应学习中,不同用户的训练样本数量可能不同,保持在不同样本数量下良好的学习效果成为需要解决的一个重要问题.提出一种自适应的草图符号识别方法,该方法采用与训练样本个数相关的分类器组合策略将模板匹配方法和SVM统计分类方法进行了高效组合.它通过利用支持小样本学习的模板匹配方法和支持大量样本学习的SVM方法,并同时利用草图符号中的在线信息和离线信息,实现了不同样本个数下自适应的符号学习和识别.基于该方法,文中设计并实现了支持自适应识别的草图符号组件.最后,利用扩展的PIBGToolkit开发出原型系统IdeaNote.评估表明,该方法可以在24类草图符号分别使用1到20个训练样本时具有较高的识别正确率和较好的时间性能.  相似文献   

11.
Relevance feedback is an efficient approach to improve the performance of content-based image retrieval systems, and implicit relevance feedback approaches, which gather users’ feedback by biometric devices (e.g. eye tracker), have extensively investigated in recent years. This paper proposes a novel image retrieval system with implicit relevance feedback, named eye tracking based relevance feedback system (ETRFs). ETRFs is composed of three main modules: image retrieval subsystem based on bag-of-word architecture; user relevance assessment that implicitly acquires relevant images with the help of a modern eye tracker; and relevance feedback module that applies a weighted query expansion method to fuse users’ relevance feedback. ETRFs is implemented online and real-time, which makes it remarkably distinguish from other offline systems. Ten subjects participate our experiments on the dataset of Oxford buildings and UKBench. The experimental results demonstrate that ETRFs achieves notable improvement for image retrieval performance.  相似文献   

12.
提出两种基于内容的音频检索的相关反馈算法,一种算法是在对正反馈图像检索技术的改进基础上提出的;另一种算法的提出是基于强制优化概念思想.实验表明,后一种算法比前一种算法具有更好的性能,并且它以一种统一的机制,充分利用了负反馈和正反馈的特性.  相似文献   

13.
相关反馈在基于内容的图像检索中成为提升检索效率的一项重要技术。然而,在图像检索中,高层语义与底层特征之间存在着巨大的"语义鸿沟",传统的相关反馈技术需要多次反馈才能获得满意结果,这使得用户的检索任务既耗时且繁琐。因此,本文通过对图像检索反馈日志信息的存储及使用过程进行分析,提出一种新的基于记忆的相关反馈策略。通过原型系统实验,与传统反馈策略相比,本文提出的策略对检索效率有明显改善。  相似文献   

14.
Zhang  Hongjiang  Chen  Zheng  Li  Mingjing  Su  Zhong 《World Wide Web》2003,6(2):131-155
A major bottleneck in content-based image retrieval (CBIR) systems or search engines is the large gap between low-level image features used to index images and high-level semantic contents of images. One solution to this bottleneck is to apply relevance feedback to refine the query or similarity measures in image search process. In this paper, we first address the key issues involved in relevance feedback of CBIR systems and present a brief overview of a set of commonly used relevance feedback algorithms. Almost all of the previously proposed methods fall well into such framework. We present a framework of relevance feedback and semantic learning in CBIR. In this framework, low-level features and keyword annotations are integrated in image retrieval and in feedback processes to improve the retrieval performance. We have also extended framework to a content-based web image search engine in which hosting web pages are used to collect relevant annotations for images and users' feedback logs are used to refine annotations. A prototype system has developed to evaluate our proposed schemes, and our experimental results indicated that our approach outperforms traditional CBIR system and relevance feedback approaches.  相似文献   

15.
A unified log-based relevance feedback scheme for image retrieval   总被引:2,自引:0,他引:2  
Relevance feedback has emerged as a powerful tool to boost the retrieval performance in content-based image retrieval (CBIR). In the past, most research efforts in this field have focused on designing effective algorithms for traditional relevance feedback. Given that a CBIR system can collect and store users' relevance feedback information in a history log, an image retrieval system should be able to take advantage of the log data of users' feedback to enhance its retrieval performance. In this paper, we propose a unified framework for log-based relevance feedback that integrates the log of feedback data into the traditional relevance feedback schemes to learn effectively the correlation between low-level image features and high-level concepts. Given the error-prone nature of log data, we present a novel learning technique, named soft label support vector machine, to tackle the noisy data problem. Extensive experiments are designed and conducted to evaluate the proposed algorithms based on the COREL image data set. The promising experimental results validate the effectiveness of our log-based relevance feedback scheme empirically.  相似文献   

16.
基于内容图像检索中相关反馈技术的回顾   总被引:25,自引:0,他引:25  
吴洪  卢汉清  马颂德 《计算机学报》2005,28(12):1969-1979
由于相关反馈技术能有效地提高基于内容图像检索的性能,使它成为图像检索系统中不可少的一部分.近年来相关反馈技术的研究正吸引着越来越多的关注,涌现出了许多算法.在简要介绍了基于内容图像检索后,文中讨论了相关反馈的交互过程和其中的重要环节,进一步分析了相关反馈中的学习问题及其特点,根据相关反馈算法所采用的检索模型把算法分为基于距离度量的方法、基于概率框架的方法和基于机器学习的方法,并在这个分类下对近年来有代表性的一些算法进行了分析和探讨,最后展望了相关反馈技术未来的发展方向.  相似文献   

17.
相关反馈技术被有效的应用于基于内容的图像检索.传统的相关反馈未能充分利用检索的历史信息.为了进一步提高检索的效率与准确性,提出一种基于历史检索信息学习的相关反馈检索方法.该方法将每次检索的结果作为历史检索信息保存.进行新的检索时,判断当前查询图像与历史检索信息的语义相关性,预测检索结果,以期减少相关反馈次数.对包含80 00幅图像的图像库实验表明,与传统相关反馈技术相比,该方法明显的改善了检索性能.  相似文献   

18.
In the last few years, we have seen an upsurge of interest in content-based image retrieval (CBIR)—the selection of images from a collection via features extracted from images themselves. Often, a single image attribute may not have enough discriminative information for successful retrieval. On the other hand when multiple features are used, it is hard to determine the suitable weighing factors for various features for optimal retrieval. In this paper, we present a relevance feedback framework with Integrated Probability Function (IPF) which combines multiple features for optimal retrieval. The IPF is based on a new posterior probability estimator and a novel weight updating approach. We perform experiments on 1400 monochromatic trademark images have been performed. The proposed IPF is shown to be more effective and efficient to retrieve deformed trademark images than the commonly used integrated dissimilarity function. The new posterior probability estimator is shown to be generally better than the existing one. The proposed novel weight updating approach by relevance feedback is shown to be better than both the existing scoring approach and the existing ratio approach. In experiments, 95% of the targets are ranked at the top five positions. By two iterations of relevance feedback, retrieval performance can be improved from 75% to over 95%. The IPF and its relevance feedback framework proposed in this paper can be effectively and efficiently used in content-based image retrieval.  相似文献   

19.
基于内容的Web图像检索引擎技术研究与设计   总被引:3,自引:0,他引:3  
提出了基于内容的Web图像检索引擎及其体系结构、数据库结构设计, 以及基于内容检索中索引建立和相关反馈的问题。在银鲨AS3000高级浏览检索系统中应用了基于内容的图像检索引擎,说明其可行性和方便易用性。文章最后展望了基于内容的Web图像检索技术的发展方向和Web图像检索技术的应用前景。  相似文献   

20.
Due to the popularity of Internet and the growing demand of image access, the volume of image databases is exploding. Hence, we need a more efficient and effective image searching technology. Relevance feedback technique has been popularly used with content-based image retrieval (CBIR) to improve the precision performance, however, it has never been used with the retrieval systems based on spatial relationships. Hence, we propose a new relevance feedback framework to deal with spatial relationships represented by a specific data structure, called the 2D Be-string. The notions of relevance estimation and query reformulation are embodied in our method to exploit the relevance knowledge. The irrelevance information is collected in an irrelevant set to rule out undesired pictures and to expedite the convergence speed of relevance feedback. Our system not only handles picture-based relevance feedback, but also deals with region-based feedback mechanism, such that the efficacy and effectiveness of our retrieval system are both satisfactory.  相似文献   

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